Just something to add to the other members' comments, re the grammar around these words: Problem and issue are often interchangeable. Trouble and difficulty are often interchangeable. So you'd say: I have a problem with this/ I have an issue with this (but you can't say 'I have a trouble' - it's not used as a countable noun). You could say. I have trouble opening this file. (in the sense of difficulty - I find it difficult to open the file.

issue, problem and trouble = generally synonymous, with some contextual difference. You can us Subject, Issue, Identity, Matter, and Concerns as syonyms which serve for the subject of your sentences. Problem, Touble, Difficulty, are also generally synonymous

They are very similar, but a little different in the way you use them in a sentence. Issue and problem are basically used the same, so you would say "It is a problem" for example, or "I'm having problems with my computer", and you can use issue the same way. "I'm having issues", "It is an issue". But trouble you would use slightly differently. You would say "It is trouble" and not "It is a trouble". And you could say "I'm having trouble" instead of "I'm having troubles". It is just a small difference. They mean the same thing, really. :)